The present invention is related to an interior structure of a water control valve for faucets, including a control valve body, a control valve stem, and a valve plug wherein the valve plug, integrally made of rubber, is equipped with a connecting end protruding at the upper side thereof to be mutually engaged with a connecting cavity of a lower switch valve thereby, and a plurality of upper and lower water sealing rings mounted at predetermined positions thereon; therefore, in the status of water supply, the upper/lower water sealing rings of the valve plug will be expanded outwards by water flow to respectively abut tight and close against the inner wall of the connecting cavity of the lower switch valve and that of a valve chamber of the control valve body for more accurate and secure mutual engagement therewith so as to achieve the best leakage-proof effect thereby.
Please refer to FIG. 1. A conventional water control valve for faucets includes a control valve body 10, a control valve stem 20, and a valve plug 30. The control valve body 10, made in a two-stepwise cylindrical shape, is equipped with a coupling end 11 disposed at the upper step thereof to be mutually engaged with a seat cover B of a faucet handle A thereby, a valve stem hole 12 properly defining the interior of the upper step thereof, a pair of positioning slide blocks 13 symmetrically extending at the upper section of the lower step thereof, and two sealing O-rings 14 mounted at the middle section of the lower step thereof. Inside the lower step of the control valve body 10 thereof is disposed a three-staged valve chamber 15 that, having a lower opening to be communicated with the valve stem hole 12 thereof, is made up of a smaller-diameter upper stage, a medium-diameter middle stage with a pair of limiting blocks 151 symmetrically protruding at the bottom edge thereon, and a larger-diameter lower stage with a pair of water outlet ports 16 symmetrically cut at proper positions thereon to be mutually connected with the valve chamber 15 thereof and with a pair of retaining grooves 161 symmetrically preset at the water outlet ports 16 thereof. The control valve stem 20 is equipped with an upper engaging end 201 to be mutually registered with the faucet handle A thereby, a plurality of water sealing rings 202 mounted at preset positions thereon, an abutting block 203 with a retaining ring 204 having a pair of symmetrical stop protrusions 2041 properly disposed thereof, and a linkage rib 205 extending at the bottom side thereon. A stop disc 21 is equipped with an elongated inserting slot 211 disposed at the center thereof and a pair of abutting flanges 212 symmetrically extending downwards at the bottom outer edge thereon. An upper switch valve 22 and a lower switch valve 23 are integrally made of ceramic material wherein the upper switch valve 22, made in an annular disc with plane edges symmetrically cut at both sides thereof, is provided with an elongated inserting recess 221 indented at the center of the top side thereon, and triangular water inlet chambers 222 each defined by an arched side tilting downwards from both cut edges to the central point thereof. The lower switch valve 23, made in a disk shape, has a pair of protrusive locating blocks 231 symmetrically disposed at both sides of the outer periphery thereof, and a plurality of quarter-shaped water inlet ports 232 distributed at the top surface thereon. The valve plug 30 is made in an annular shape, having a water inlet hole 31 disposed at the center thereof, a coupling end 62 extending at the upper side thereof, a positioning flange 33 extending at the lower side, and an upper packing ring 321 and a lower packing ring 322 mounted at the upper and bottom sides thereof respectively.
Please refer to FIG. 2. In assembly, the control valve stem 20 is joined to the valve chamber 15 of the control valve body 10 thereof, permitting the upper engaging end 201 thereof to extend outside the valve stem hole 12 of the control valve body 10 and the abutting block 203 to locate precisely between the limiting blocks 151 thereof for movement limited within 90 degrees therein. Then, the stop disc 21 is placed into the valve 15 of the control valve body 10 with the inserting slot 211 mutually engaged with the linkage rib 205 of the control valve stem 20, and the upper switch valve 22 in turn is located into the valve chamber 15 thereof with the inserting groove 221 thereof precisely mated with the linkage rib 205 of the control valve stem 20 thereof and the plane edges cut at both sides thereof closely joined to the abutting flanges 212 of the stop disc 21 respectively. The lower switch valve 23 is then guided to the valve chamber 15 till the protrusive locating blocks 231 thereof precisely inserted to the retaining grooves 161 of the control valve body 10 thereof, permitting the upper switch valve 22 to abut closely on top of the lower switch valve 23 thereof. Finally, the coupling end 32 of the valve plug 30 is joined to the valve chamber 15 thereof, permitting the upper packing ring 321 mounted at the coupling end 32 thereof to abut closely against the bottom surface of the lower switch valve 23 and the positioning flange 20 precisely abut against the bottom outer edge of the control valve stem 20 to complete the assembly thereof.
In practical use, the water inlet chambers 222 of the upper switch valve 22 are wide open for the discharge of water. Water coming out from a water inlet pipe C will go through the water inlet hole 31 of the valve plug 30 and flush upwards at the underside of the lower switch valve 23 to flow out through the water inlet pores 232 of the lower switch valve 23 and come into the water inlet chambers 222 of the upper switch valve 22 thereof. Finally, the water flowing out from the water inlet chambers 222 will go through the water outlet holes 16 of the control valve body 10 to be discharged there-from via water outlet pipes to complete the water supply thereof. When the water inlet chambers 222 of the upper switch valve 22 are in a closed-off status, the water inside the water inlet chambers 222 is cut off from the water outlet holes 16 of the control valve body 10 without any water flowing out from the water outlet pipes to shut off the water supply thereof.
However, there are some drawbacks to such conventional water control valve structure for faucets. First, the upper packing ring 321 of the valve plug 30 is simply contacted and abutted against the bottom surface of the lower switch valve 23, which, poor in the mutual engagement thereof, is prone to produce gaps and result in the problem of water leakage. Thus, the conventional water control valve structure is featured by a bad leakage-proof effect. Second, when the control valve body 10 is mounted to the seat cover B of the faucet handle A, the downwards pressure will force the lower packing ring 322 thereof to abut tight against the inner bottom edge of the water inlet pipe C and the upper packing ring 321 to press closer at the bottom surface of the lower switch valve 23 thereof. Under the impact of high water pressure on and off in a long time, the upper and lower switch valves 22, 23 tend to get squeezed and crushed up into pieces.